© New Zealand Broadcasting School 2020

"Auckland is the city with the cleanest air in the world"

Emma Olsen
Auckland City
Auckland City   wikimedia

An air quality scientist looks into Auckland's air quality difference since lockdown started.

Three weeks into New Zealand's nationwide lockdown, Auckland City is seeing significantly cleaner air.

Principal Air Quality Scientist Dr Ian Longley has looked into the differences prior to and during the lockdown. 

"The levels of nitrogen dioxide were high enough to exceed guidelines set by the World Health Organisation a month ago. Now, with a large reduction in traffic pollution, if I were to visualise it, Auckland is the city with the cleanest air in the world."

One week into lockdown, Longley looked at the figures for oxides of nitrogen, the best measure of all traffic exhaust pollutants in Auckland. The levels were reduced by 51% at Queen Street, 62% on Lincoln Road and 65% in Takapuna.

Three weeks in, he re-looked at the figures and found that concentrations of nitrogen dioxide were still reducing. Lincoln Road has majorly reduced by 89% and Takapuna by 88%. 

"Because we are not exposed to the emissions of neighbouring cities or countries, the significant improvement is due to the massive reduction in traffic congestion," said Longley.

If Aucklanders continue with their low levels of driving, the improvements should be maintained. Although he questions if this will even be an option for Auckland residents.

"If and when the lockdown ends, our air quality will broadly reflect the state of the economy. Can people still afford to drive?"

Longley hopes once the lockdown is over, people will see the differences and actively make a change because our air quality is in their power. 

"We are all experiencing visibly cleaner air, the kind you see in images to lure tourists. If you have views to a distant horizon, the Coromandel across the Gulf, for instance, it is clear every day. Hopefully, Aucklanders will realise how much they treasure that."

Ironically, given that we are hiding from a killer virus, the air quality makes Longley feel healthy as well as comforted that the arguments as to how we achieve clean air are now going to be a little easier.